Saw two guys setting a slack line up to the top of the Bluffs at Araps today from the rap anchors above Missing Link. Anchors have been placed on the opposite cliff for the exercise. My concerns were:

1. Cross loading of the rings above Missing Link.
2. Rigging of the W anchors as an 'American Death Triangle'

This may seem unimportant to the people involved, but cross loading of the ringbolts affects not only the capacity of their anchors but also the safety of the anchors for subsequent users. The way they rigged the W anchors indicated they had a poor understanding of safe use of anchors. If anyone catches up with these guys, or knows them, please help to educate them.

On 14/03/2012 sliamese wrote:>What do u mean by W anchor? Typically ive only ever hears that referring>to three pieces equalised? >>Do people get that an american death triangle will put about 140% of the>load onto EACH anchor?

Re; the 'cross-loading' . . .
I imagine he means pulling horizontally at an angle to the vertical plane . . .
This could put a large twisting force on the shaft - potentially quite a problem.
For glue-in rings - being in tension is less of a problem unless overloaded . . .

On 14/03/2012 Macciza wrote:>Re; the 'cross-loading' . . .>I imagine he means pulling horizontally at an angle to the vertical plane>. . .>This could put a large twisting force on the shaft - potentially quite>a problem.>For glue-in rings - being in tension is less of a problem unless overloaded>. . .

That is cross loading. Cross loading any ring bolt, either industral or recreational, is not recommended. They are designed for forces parallel to the line of the ring (+/- 20 degrees normally). W also means west. The major concern is the use of the rap anchors for the line, as highlines generate very high forces on anchors and could be potentially compromising the rap anchors which others are going to use later. Would hate that to be the cause of an accident. The 'death triangle' rigging is just an example of poor understanding of rigging concepts and poor judgement.

One issue I noted above Eskimo Nell is that the Petzl rings there appeared to have been used by the slackliners. One had obviously been crossloaded where the ring was exhibiting some deformation and damage. Have yet to check the anchors above Missing Link. Will report back on this when further information comes to hand.

Sheesh! Defirmation on the petzl ring? I'd be keen ti see a photo next time you are up that way.
Given the manufacturer stamping of 25kN and 50kN there must have also been deformation on the connectors used, unless they were using quicklinks and burly ones at that.
Also remeber that the test data is done on concrete (i think 50mpa). I am surprised that if the ring deformed it didn't also start to seperate from the rock.

By cross loading you are talking about putting the rings into a shear load situation across the eye, no? I always thought cross-loading a ring or eye bolt meant it had two opposing loads applied at once? You can't 'cross-load' anything with only one force vector as a slackline would impose. I could be wrong here, my engineering degree was more about booze and parties than going to class - Ollie, Damo, anyone else want to correct me?

In any case this whole slackline/highline craze can go stuff itself if they're gonna throw bolts in all over the show. I don't remember any ring farm near Esky Nell. These are what should be chopped, not rap anchors!

On 18/04/2012 Sonic wrote:>By cross loading you are talking about putting the rings into a shear load>situation across the eye, no? I always thought cross-loading a ring or>eye bolt meant it had two opposing loads applied at once? >Ollie, Damo, anyone else want to correct me?

Look, everyone understands the situation you are calling "cross loading", and the situation the good doctor is calling "cross loading"........arguing over terminology is silly.

>In any case this whole slackline/highline craze can go stuff itself if>they're gonna throw bolts in all over the show. I don't remember any ring>farm near Esky Nell. These are what should be chopped, not rap anchors!

I've been struggling with the ethics of this one. I expect all climbers to harden up, build belays, scramble on approaches/descents, and generally be able to take care of themselves without it all being laid out on a platter for them. I have no such expectation of non-climbers. If these dudes are truly outside of the climbing scene and it's ethics and ideas.....then do climbers have any grounds to tell them what they can and can't do?

>I've been struggling with the ethics of this one. I expect all climbers>to harden up, build belays, scramble on approaches/descents, and generally>be able to take care of themselves without it all being laid out on a platter>for them. I have no such expectation of non-climbers. If these dudes are>truly outside of the climbing scene and it's ethics and ideas.....then>do climbers have any grounds to tell them what they can and can't do?

As far as I see it the ethics of it all is that we should smash them so fukin hard they don't dare come back.

I'm going to place some bolts to set up a washing line between D Major and Diapson so I can hang my washing out at there next week. Of course, Damo won't be objecting to it because he's suddenly gone all cultural relativist on us.

I'm at Brooyar near Brisbane and there is a bunch of slackliners setting up between two buttresses. I explained to them the difference between the loads we put on anchors, and the loads they put on anchors. Once I explained I was a rigger and climbed for 16 years, They listened and I think they are changing how they rig.